Features include:

•RPG gameplay in which players work their way through challenges they can level characters up with experience points.
•Two separate storylines, one featuring Bowser as a playable character, and the other revolving around the microbe-sized Mario, Luigi and Peach.
•Integrated gameplay action which the player toggles between, where Mario and Luigi must solve puzzles and challenges behind the scenes to help Bowser overcome various obstacles and advance the plot.
•DS/DSi integrated gameplay in which players must turn their Nintendo DS/DSiDSi system sideways, blow into the microphone or tap on the touch screen with the stylus to keep up with the action.
•Distinctive Nintendo humor featuring the same hilarious dialogue that has been the hallmark of the Mario & Luigi series.